The invention relates to a telecommunication apparatus having power supply terminals for supplying power to a peripheral which has an electrical signature and a recognition device for recognizing a peripheral connected between said terminals.
The invention likewise relates to any other apparatus having power supply terminals for supplying power to a peripheral which has an electrical signature and a recognition device for recognizing a peripheral connected between said terminals.
The accessories or peripherals of portable telephones which are currently available on the market for various specific applications (hands-free kit, portable computer, fax, etc.) do not all function with the same supply voltage. Moreover, certain of these accessories are adapted to a telephone model or to a particular maker. For correctly supplying power to these various peripherals, the main apparatus thus has a connector with various pins among which a supply pin, a ground pin and as many dedicated pins as there are peripherals likely to be connected to said apparatus. Indeed, it is absolutely necessary to identify these accessories during their connection via a specific identification pin so as to avoid an unadapted voltage being applied to them and running the risk of damaging them.
An apparatus comprising an identification device which permits of identifying various types of batteries via a unique identification pin is already known. It works with standardized power supply batteries which have a characteristic identification resistor and an identification pin.
If this system provides the advantage of utilizing a unique identification pin (in addition to the two power supply pins) for recognizing a peripheral (a battery in this case), it has nevertheless drawbacks. The system indeed requires that the main apparatus comprise a microcontroller and that all the peripherals comprise a characteristic identification resistor whose value is preprogrammed in the microcontroller. Moreover, the system makes it necessary to reserve a specific identification pin among the pins available on the connector of the main apparatus. The connectors provided on most of the telecommunication apparatus are already full and the reservation of an identification pin forces one to use connectors with a large number of pins.
Thus, it is no longer possible to connect new peripherals without increasing the number of pins of the standard connectors.